Creation of Composite Optical Elements by the Ion-Beam Surface-Activation Method for Laser Applications

A method for creating composite active elements from dissimilar optical materials, which consists in treating surfaces with a beam of heavy argon ions and forming an optical contact between the surfaces, is implemented and tested. Composite active elements Yb:YAG/YAG and Yb:YAG/sapphire in the geometry of a thin disk are created. The elements are tested in a high-average-power laser scheme. Lasing with a differential efficiency of 48% at at a power of more than 100 W is obtained using the Yb:YAG/sapphire element, while the lasing efficiency for the Yb:YAG/YAG element is 39%, which is a consequence of more efficient cooling of the active medium through sapphire.